Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753460AbaLDJep (ORCPT ); Thu, 4 Dec 2014 04:34:45 -0500 Received: from mail.kmu-office.ch ([178.209.48.109]:36288 "EHLO mail.kmu-office.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753168AbaLDJen (ORCPT ); Thu, 4 Dec 2014 04:34:43 -0500 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Date: Thu, 04 Dec 2014 10:36:55 +0100 From: Stefan Agner To: Sanchayan Maity Cc: a.zummo@towertech.it, rtc-linux@googlegroups.com, shawn.guo@linaro.org, linux-kernel@vger.kernel.org Subject: Re: [RESEND PATCHv2] drivers/rtc/rtc-snvs: Add clock support In-Reply-To: References: Message-ID: User-Agent: Roundcube Webmail/1.0.3 X-DSPAM-Result: Whitelisted X-DSPAM-Processed: Thu Dec 4 10:34:04 2014 X-DSPAM-Confidence: 0.9899 X-DSPAM-Probability: 0.0000 X-DSPAM-Signature: 54802a8c12811866636528 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2014-12-03 06:58, Sanchayan Maity wrote: > This patch adds clock enable and disable support for > the SNVS peripheral, which is required for using the > RTC within the SNVS block. > > The clock is not strictly enforced, as this would > break the i.MX devices. The clocking for the i.MX > devices seems to be enabled elsewhere and enabling > RTC SNVS for Vybrid results in a crash. This patch > adds the clock support but also makes it optional > so Vybrid platform can use the clock if defined > while making sure not to break i.MX . > > Signed-off-by: Sanchayan Maity > --- > drivers/rtc/rtc-snvs.c | 34 ++++++++++++++++++++++++++++++++-- > 1 file changed, 32 insertions(+), 2 deletions(-) > > diff --git a/drivers/rtc/rtc-snvs.c b/drivers/rtc/rtc-snvs.c > index fa384fe..d4a6512 100644 > --- a/drivers/rtc/rtc-snvs.c > +++ b/drivers/rtc/rtc-snvs.c > @@ -17,6 +17,7 @@ > #include > #include > #include > +#include > > /* These register offsets are relative to LP (Low Power) range */ > #define SNVS_LPCR 0x04 > @@ -39,6 +40,7 @@ struct snvs_rtc_data { > void __iomem *ioaddr; > int irq; > spinlock_t lock; > + struct clk *clk; > }; > > static u32 rtc_read_lp_counter(void __iomem *ioaddr) > @@ -260,6 +262,18 @@ static int snvs_rtc_probe(struct platform_device *pdev) > if (data->irq < 0) > return data->irq; > > + data->clk = devm_clk_get(&pdev->dev, "snvs-rtc"); > + if (IS_ERR(data->clk)) { > + data->clk = NULL; > + } else { > + ret = clk_prepare_enable(data->clk); > + if (ret) { > + dev_err(&pdev->dev, > + "Could not prepare or enable the snvs clock\n"); > + return ret; > + } > + } > + > platform_set_drvdata(pdev, data); > > spin_lock_init(&data->lock); > @@ -280,7 +294,7 @@ static int snvs_rtc_probe(struct platform_device *pdev) > if (ret) { > dev_err(&pdev->dev, "failed to request irq %d: %d\n", > data->irq, ret); > - return ret; > + goto error_rtc_device_register; > } > > data->rtc = devm_rtc_device_register(&pdev->dev, pdev->name, > @@ -288,10 +302,16 @@ static int snvs_rtc_probe(struct platform_device *pdev) > if (IS_ERR(data->rtc)) { > ret = PTR_ERR(data->rtc); > dev_err(&pdev->dev, "failed to register rtc: %d\n", ret); > - return ret; > + goto error_rtc_device_register; > } > > return 0; > + > +error_rtc_device_register: > + if (data->clk) > + clk_disable_unprepare(data->clk); > + > + return ret; > } > > #ifdef CONFIG_PM_SLEEP > @@ -302,16 +322,26 @@ static int snvs_rtc_suspend(struct device *dev) > if (device_may_wakeup(dev)) > enable_irq_wake(data->irq); > > + if (data->clk) > + clk_disable_unprepare(data->clk); > + > return 0; > } > > static int snvs_rtc_resume(struct device *dev) > { > struct snvs_rtc_data *data = dev_get_drvdata(dev); > + int ret; > > if (device_may_wakeup(dev)) > disable_irq_wake(data->irq); > > + if (data->clk) { > + ret = clk_prepare_enable(data->clk); > + if (ret) > + return ret; > + } > + > return 0; > } > #endif Acked-by: Stefan Agner -- Stefan -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/